An integrated bearing assembly is provided, comprising a bearing housing defining
an axial cavity in which a shaft is disposed. The shaft is rotatably supported
by at least two bearing sets. The axial cavity defines three regions, each having
distinct diameters. A pair of first regions defines cavity diameters sufficient
to receive the bearing sets. A pair of second regions defines cavity diameters
such that a small gap is defined between the inner surface of the cavity and the
shaft. The third region cooperates with the shaft to define a cylindrical volume
containing a coolant. Wettable coatings are utilized in the cylindrical volume
to allow free flow of, and maximum contact with, the coolant. Non-wettable coatings
are provided in the second regions to contain the coolant. The second regions also
function as bearing spacers, thus simplifying bearing assembly design, assembly,
and performance.